FIGURE 8 in Gephyrocharax machadoi, a new species of Stevardiinae (Characiformes: Characidae) from the Rio Paraguai basin, central Brazil

FIGURE 8. Spermatozoon of Gephyrocharax machadoi. A,B,C,F: Longitudinal sections. D,E,G,H,I,J,K,L: Cross sections. A,B: Granular chromatin is present in the nucleus (n), which is drop-shaped and elongated towards the flagellum (f). The midpiece contains elongated mitochondria (m) and vesicles (v). C,D,E: The nucleus has two lobes that involve the initial portion of the flagellum (f). F: The double nuclear fossa (arrow) partially houses proximal centriole (p) which is anterior and forms an acute angle in relation to the distal centriole (d). G,H,I,J,K: Section of anterior portion of nucleus (n) that displays mitochondria (m). Inside letter I is the axoneme with classical pattern of microtubules (9+2). L: Note the presence of the cytoplasmic sleeve (arrowhead). Asterisk: cytoplasmic canal. Bars: A,B,C,D,E,F: 1 µm. G,H,I,J,K,L: 0.6 µm.